Thermostatic cooling system for internal-combustion engines.



F. J. RAYFIELD.

THERMOSTATIC cooums SYSTEM FOR INTERNAL comausnou ENGINES.

APPLICATION FILED APK- l8. I9,- 1 ,273,406. Patented July 23, 1918.

- 4 5HEETSSHEET xfkssq x Rea end -]fa 1/' Zd W gs F. J. RAYFIELD.

THERMOSTATIC cooum; SYSTEM FOR INIERNAL pornsusnou ENGINES.

APPLICATION FILED APR. I8. 1911.

F. J. RAYFIELD.

THERMOSTATIC COOLING SYSTEM FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED APR. 18. Hill.

1,273,406. Pa tented July 23, 1918.

4 SHEETS-SHEET 3.

Im/entir F. l. RAYFIELD.

THERMOSTATIC COOLING SYSTEM FOR INIERNAL COMBUSTION ENGINES.

APPLICATION FILED APR. w. Hill.

1 273,406. Patented July 1918.

4 SHEETS-SHEET 4.

FREDERICK J. RAYFIELD, OF CHICAGO, ILLINOIS.

THERMOSTATIC COOLING SYSTEM FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented July 23, 1918.

Application filed April 18, 1917: Serial No. 163,059.

To all whom it may concern:

Be it known that I, FREDERICK J. RAY- FIELD, citizen of the UnitedStates, residing at Chicago, in the county of Cook and State ofIllinois, have invented certain new andand exact description as Wlllenable others skilled in the art to which it appertains to make and usethe same.

This invention relates to improvements in internal combustion engines,and more particularly to means for regenerating the temperature of thecylinders thereof and radiators therefor to the end that the highestmotor eiiicienc y may be'developed in the shortest possible periodfollowing the starting of the motor when cold, and continuouslymaintained after the motor has become warmed up. This includes obviouslythe prevention of freezing of the water in the radiators and waterjacket of the motor in extremely cold weather, and the saving of fueland thermal units, and the effecting of an increase in power inproportion to fuel consumption due to the maintenance of the propertemperature of the motor cylinders during operation thereof.

The invention also has for its object to provide thermally controlledmeans for automatically effecting a switch from a low gravityhydro-carbon to a higher gravity hydro-carbon as soon as the motor shallhave attained such a temperature as will adapt it to the consumption ofthe higher gravity fuel.

Other minor objects of the invention will appear from the followingspecification.

In the accompanying drawings illustrat- 111g; suitable embodiments ofthe invention:

Figure 1 's a side elevation of an internal combustion engine andradiator and cooling system applied thereto, parts of the exhaustmanifold being broken away.

Fig. 2- is a sectional view on the line 2-2 of Fig. 1-.

Fig. 3- is a section on the line 33 of F ig. -2.

Fig. -4 is a top plan of a housing for the thermostat and the associatedparts.

I do hereby declare the followa Fig. 5- is a cross-section on the line55 of Fig. 1.

Fig. -6- is an elevation of a modified form of an explosion engine andcooling means.

Fi -7 is a slightly modified form of housing for the thermostat.

Fig. --8- is a detail section on an enlagged scale on the line 8-8 of Fi-7.

1g. -9 1s a fragmentary detafi section on an enlarged scale on the line9-9 of Fig. 1-.

ig. 10- is a fragmentary top plan view of the parts shown in Fig. 9.

Fig. 11 is a fragmentary detail section on an enlarged scale on the line11-11 of Fig. 10-.

Fig. 12 is a fragmentary detail vertical section showing a -valveoperating connection.

Fig. -13 is a view similar to Fig. -1 showing another embodiment of theinvention.

Fig. 14 is a view similar to Fig. -1 partly in section showing theinvention embodied in a marine engine.

Similar numerals and letters refer to similar parts throughout theseveral views.

.The preferred embodiment of my invention as applied to the en ine of amotorpropelled vehicle equipped with a watercooled motor and radiator isillustrated in the drawings and set forth in this specification, and isnot limited to the employment of any particular means for moving thecooling medium through the cooling system.

A thermo-slphon system is efficient, but a forced circulation system ispreferred.

The invention comprchcnds the employment of a circulation system -whichincludes means for automatically causing the cooling liquid to be passedinto heat-absorbing relation to means for quickly raising thetemperature thereof to the desired point or approximating the same andthereafter causing the same to circulate in whole or in part through thewater jackets of the cylinders, the part thereof not circulating throughsaid jackets being deflected through the first named part of the system.

The invention as thus broadly defined may be variously embodied and suchemments, types and purposes, as will be obvious, the several embodimentsshown and described being intended only to illustrate examples of theapplication to what may be' termed standard modern equipments.

In the type of construction illustrated in Fig. 1' the motor cylinders 1formed integral with each other in a single casting, are equipped with awater-jacket 2 which 1s connected with the radiator 39 by means of apipe 41 leading from the lower end of the radiator to the inlet end of apump 28 of any suitable type, a pipe 29, valve-housing 19 and pipe 33.The said water-jacket 2 is connected with the upper end of the radiatorby means of the pipe or manifold 37.

Water from the lower end of the radiator passes into the valve-housing19 through the inlet port branch 27 of the latter which connects withthe pipe 41. The pipe 33Qconnects with the outlet assage 14 of the saidhousin s, thelatter being also provided with an out et passage 15 whichconnects with a pipe 43 through which water is adapted to pass into apipe or duct adapted to be heated by the hot products of combustion ofthe motor, and which communicates with the pipe or manifold 37contiguous to its connection with the upper end of the radiator.

The flow of water through the outlet passages 14 or15 is controlled bymeans of a single double-faced valve 17 pivotally mounted within saidhousing and adapted to seat alternately on the valveseats 23 and 24 atthe mouths of said passages. When the .valve 17 is seated on the valveseat 23, the water will circulate through the water' jacket 2, and whensaid valve is seated on the valveseat 24, the water will circulatethrough the pipes 43 and 46 and pass in to the radiator, It beingobvious that the circulation may be partially both ways when the valveis disposed at any point between the seats 23 and 24.

The shaft 18 carrying the valve 17 is disosed in a small chamber of thehousing and 1n one embodiment or-adaptation of the in-.

vention projects through a wall of the latter for purposes hereinafterdefined.

The said valve 17 is actuated by means of athermostat A comprising thebellows-diaphragm of well-known construction filled with a volatileliquid having a high coeflicient of expansion hermetically sealedtherein. The cup 01' housing 8 of said diaphragm is equipped with abridge 9 which is anchored to one end of the diaphragm by .means of acylindrical projection 10 which is reciprocably and universally movablewith respect to the bridge 9. At its opposite end the diaphragm hasfixed thereto a stem 11 which is disposed and slidable in the bore 12 ofthe boss 13 of the housing 8 which is preferably integral with the valvehousing 19 which is cast in two parts suitably secured together toprovide a water-tight oint. The stem 11 of the diaphragm'is hollow andreceives a piston 5 mounted at the end of a piston rod 6projectingfromthe outer end of the stem and which is reciprocablymovable with respect to said stem against the action of the springs 7and 8 bearing upon opposite ends of the piston and opposite end Wallsofsaid stem 11. The valve 17 is connected with the outer end of thepiston rod 6 by means of the link 20' and p ns 21 and 22. Thisarrangement enables the diaphragm to expand and contract respectivelywhen the valve is seated on the valve-seats 23 and 24 and obviates unduestrains on the said diaphragm.

The housing 8 is suitably mounted on the wall 31 of the water jacket 2bordering an opening therein in such manner as to provide a water-tightjoint, the bridge 9 and a portion of the diaphragm 8 projecting intosaid water jacket 2 so that the expansion and contraction of thediaphragm will be controlled by the water contained within the diator39, pump 28 and pipe 29. The pipe 46 is, in Fig. 1, shown as passingthrough the exhaust manifold 45 so that the water is very quickly heatedto a temperature for examplelof one hundred and eighty degrees Fahr.Meanwhile the water in the acket 2 will'be heated to some extent thusexpanding the diaphragm A and causing it to exert pressure on the piston5 through the medium of the spring 7. Movement of the stem 11 to eifectthis is resisted by the spril'ig-pre'ssed 1 ball 26 engaging in therccess 53 in the stem 11, but as soon asthe force of expansion of thediaphragm is suflicient to overcome that resistance the valve 17 will hesuddenly moved from seat 24 toward seat' 23 or upon the latter.

If the valve 17 is disposed between the limits of its movement thecirculation of'the liquid will be partly through the jacket 2 and partlythrough the pipe 46, thus admixing the hotter water in the radiator withthe cooler water in the water-jacket, or vice versa. Except inextremelycold weather it is more probable that the water inthe radiatorwill now be hotter than the water inthe jacket 2, and when admixed withthe latter further rapid expansion of the diaphragm" to cause the valveto seat on the valve-seat 23 so that thereafter all water will circulatethrough the jacket 2.

If the heat radiation in the latter exceeds absorption from thecylinders as might occur when the motor is running very slowly, a dropin temperature will result which will cause the valve 17 to moveslightly from.

the seat 23 and thusefi'ect a circulation of liquid through the pipe 46.The water trapped in the latter will obviously be very much hotter thanthe. water in the jacket 2 and radiator 39, and will now become admixedwith the latter and raise its temperature to someextent, but if notsufficient to cause the valve 17 toreturn to seat 23 the continuedpartial circulation through pipe 46 will suflice to supplementheat-absorption from the cylinders to effect raising of the temperatureto the point necessary to cause said valve 17 to return to seat 23. Oron the other hand, under certain conditions the valve 17 may remaindisposed between both seats as. will be obvious.

The compression spring 51 bearing on the ball 50 is adjustable by meansof the thumb screw 52 to regulate the force with which ball 49 seats inthe recess 53 in stem 11.

The lock nut 54 secures the thumb-screw 52 against movement.

Mounted on the shaft 18 of the valve 17, and with which the latter isrigid, is an indicating hand which indicates on a graduated scale on adial 71 suitably secured to the valve housing 19. This hand will indicate whether the valve is seated on either of the valve seats 23 or24, or whether it is positioned between said seats.

The said shaft 18 also carries a lever 72 rigid therewith which, ashereinafter described, may be connected with a valve con trolling theconnection of the carbureter with two sources of supply of hydro-carbonliquids of different specific gravity,such connection being moreparticularly illustrated in the embodiment shown in Fig. 13.

In order that when the circulation of the cooling medium is confinedentirely to the water jackets of the cylinder and radiator there may beno back-flow through the pipes 47 46 and 43 and against the 'valve 17,and thus through the valve easing into the Water jackets, .I provide acheck-valve 68 contiguous to the connection between the said pipe 47 andthe conduit 37 which will permit the free flow of liquid into the latterfrom the pipe 47, but will prevent its return flow.

The embodiment illustrated in Figs. 1, 2 and 3 is designed forincorporation in the factory where the auto mobile is made, and in Fig.6 I have shown my invention embodied in what might be termed a retailequipment adapted to be supplied to automobiles already in the hands ofthe user. In that event there would be no opening through the outer wallof the water jacket through which the bridge 9 of the diaphragmhousingcould extend. Accordingly, an entirely inclosed housing 58 is providedwhich is in part integral with the valve housing 9, and is connected bymeans of the pipes 62 and 66 with the pump and the conduit 37 so as tocause a portion of the water delivered from the pump or enteringthe-inlet end-of the same to be passed through the said housing 58. Theoperation of this embodiment is exactly the same as that shown in Figs.1-, 2 and 3 so that further description will be unnecessary.

It is desirable, of course, that the diaphragm may be adjusted to someextent with respect to its anchorage in its housing, and in Figs. -7-and 8 I have illustrated means for effecting such an adjustment with "aview to more accurately regulating the respective temperatures at whichthe valve 17 will seat on the valves 23 and 24 respectively. It will benoted that at one end of the diaphragm there is mounted a cylindricalprojection provided with an external annular groove of somewhat greaterwidth than the thickness of the end wall of the housing. The housing isprovided with an opening through which the said projection extends theperipheral wall of the opening being received in the annular groove insaid projection which is reciprocably movable with respect to said endwall. It is further desirable that said projection shall have sufficientfreedom of play to accommodate itself to unequal expansions of thediaphragm and, therefore, the fit in the opening is made relativelyfree. The outer end of said projection is provided with a diametric slot74 which extends through the end flange thereof, and partly through thecylindrical wall thereof, and receives a plate 75 mounted upon the endof a threaded shank 76 which projects through a cap 77 mounted on athreaded flange 78 projecting from the end wall of the housingconcentric with the opening therein, and which effects a water-tightseal for said end of said housing, said threaded shank being adjusted bymeans of a lock nut 79 in a well-known manner.

It is desirable in at. least certain classes of internal combustionengines to employ relatively high gravity hydro-carbon liquids in laceof low gravity after the motor is $11 ciently hot to effect propervaporization and carburetion of such heavier liquid, and I contemplatethe employment of the thermostatic control hereinbefore described toautomatically effect the change of fuel as the motor becomessufliciently heated to engines of this type are connected so as to takewater from the body in which the boat is floating, and is passed aroundthe exhaust Lush:

efficiently consume the same. Thus two sources of supply of hydro-carbonliquids be substituted to the extent of a difierent of differentSPGClfiC gravities may be provided, one of which connects with the pi e80, and the other with the pipe 81, both said pipes leading t-o'athree-way valve housing 82 connectedby means of pipe 84 with thecarbureter. The stem 85 of the three-way valve is connected by means ofa rod 86 with the said lever 72 so that when the latter is seated on thevalve seat 23, at which time the cylinders will be sufli ciently hot toefliciently consume the higher gravity fuel, the latter will be suppliedto the carbureter in place of the lower gravity and vice versa.

Referring again to Figs. 1 to 6-- inclusive, it Wlll be observed thatthe pipe 46 when shut off from the circulating system by the seating ofthe valve on the seat 23 will contain water exposed in heat-absorbingrelation to the hot products of combustion exhausted from the cylinders,and said water will obviously in time become very hot and possiblygenerate steam. This steam would, of course, be exhaustedthrough thecheck valve into the radiator, and would merely effect an increase intemperature of all of the liquid in the circulating system. This might,however, in some instances, be objectionable, and, therefore, theembodiment shown in Fig. 13 mlght arrangement of the pipe 46, that is tosay, instead of passing the pipe 46 through theexhaust manifold a branchexhaust pipe 87 may be connected with the exhaust manifold opposite theexhaust port of one of the cylinders of the engine. A water jacket 88may surround a portion of said branch exhaust pipe 87, and interposed inthe pipes corresponding to the pipes 43 and 47 of the structure shown inFig. 1-, so that the water is circulated around said branch pipe 87 whenthe valve 87 is seated on the valve seat 24. Interposed in the branchexhaust pipe 87 is a butter-fiy valve 89, the stem 90 of which isconnected by means of the rod 91 with the arm 72 on the shaft 18' ofsaid valve 17 so as to efiect closure of the pipe 87 when thetemperature of the cooling liquid has been raised to the desired extent,and the circulation is deflected from the water jacket 88 and throughthe water j ackets of the cylinders.

In Fig. 14 I have shown my invention embodied in a marine type internalcombustion motor, wherein the conditions to be met difl'er materiallyfrom those of motor propelled vehicles for use on land.. Generallyspeakingthe water jackets of marine manifold, and thence through thewater aaraeoe jackets and back into the body of water. This obviouslytends to maintain the cylinder temperatures too low, or in the eventthat the circulation of water is temporarily interrupted, may cause thetemperaturev within the cylinders to rise to too high a point. Myinvention is adapted to overcome these difliculties, but-theembodimentdifi'ers as aforesaid to the extent necessary to obtain thedesired results. 7

In this embodiment the pump-92 is connected at its inlet end by means ofthe pipe 93 with the body of water in which the boat is floating. Theoutlet end ofthe pump is connected by means of the pipe 93 with thevalve casing 19 constructed the same as that shown in Figs. 2 and -3 Oneside of the valve casing is connected by means of a pipe 94 with a waterjacket 95 sur rounding the exhaust manifold 96, and from the said waterjacket 95 a pipe 97 leads to a valve-housing 98 similar to the valvehousing 19 and provided with an oscillating valve 99 adapted to seat oneither of two valve seats. One of the latter is at the mouth of anexhaust pipe. 100 throu h which water is discharged back into t e bodyfrom which it is received, and the other, 101, connects with the waterjackets through a check-valve casing 102. The said" check valve casingis provided with two check valves 103 and 104 respectively, the formerpermitting free flow from the pipe 101 into the water jackets, and thevalve- 104 preventing flow through the pipe 105. The latter is connectedwith the other side of the valve housing 19, and is adapted'to causewater to pass rom said valve housing directly through the check valvecasing 102 past the check valve 104 into the water jacket. As it isdesirable in this class of motors that the exhaust manifold bemaintained cool, it is inadvisable to entirely shut ofl the circulationof water through the water jacket 95, and for this purpose a by-v passpipe 106 is provided which connects the pipe 93 with the pipe 94 and isprovided with a valve 107 which may bead usted to regulate the volume offlow past the valve housing 19 when the valve is seated to cut off flowthrough the pipe 94.

The diaphragm housing 108 is connected by means of a pipe 109 with theump 92 and by means 0 a pipe 110 with t e water jacket.

Marine engines are not required to meet the same conditions of serviceas engines of motor propelled vehicles on land for the reason that theyare under a far more constant load for av longer period, and arewater-cooled instead of air-cooled. Hence, the only object tobeaccomplished by this invention is to prevent the marine engine frombeing maintained too cool by a too steady flow of water through thewater jackets thereof, but to maintain the temperature of the enginevery uniform.

The operation of the invention when applied to marine motors is, owingto the unlimited supply of water for cooling pur-' poses, somewhatdifi'erent from that of the and engine. It will be seen that in startingthe motor the valve 18 will be positioned to cause the water to passfirst to the water jacket 95, and thence through the water jackets ofthe cylinders, and thereafter back into the bod of water from which itis received. T e water is primarily heated by the exhaust pipe, and its'temperature further increased by absorption of heat from the cylinders.As the heat of the engine increases the circulation of water passinthrough the water jackets is cut oil mm the water jacket 95 around theexhaust pipe, and only a small quantity enters the latter from theby-pass pipe around the valve-casing 19.

As previously stated the invention may be varlously embodied to adapt itto engines for various purposes and used under v rying conditions, butall such modificat ons in construction as may be necessary to adapt theinvention to such various purposes are comprehended within the scope ofthe invention as defined in the appended claims.

I claim as my invention:

1. In a cooling system for internal combustion engines equipped withwater-jackets, a source of supply of a cooling liquid, means other thanthe water-jacket of the cylinders for heating the said liquid, means foreffecting circulation of the liquid through the water-jacket, and inheat absorbing relation to said heating means, and thermally controlledmeans for shutting off the circulation of liquid through one or theother of said means or efi'ecting circulation thereof partly throughboth in accordance with variations in temperature H of said liquid.

2. A cooling system for internal combustion engines includingwater-jackets for the engine cylinders, a water conduit associated withthe exhaust manifold for heating water by means of the hot products ofcombustion, a source of supply of a liquid adapted to circulate throughsaid jackets and said conduit, and thermally controlled means forcausing the water to circulate either through said conduit or saidjackets or simultaneously through both.

3. A cooling system for internal combustion engines includingwater-jackets for the engine cylinders, a water conduit assoclated withthe exhaust manifold for heating water by means of the hot products ofcom-' bustion, a source of supply, of a liquid adapted to circulatethrough said jackets and said conduit, and means controlled by thetemperature of the liquid contained in said jackets for causing thewater to circulate either through said conduit or said jackets orsimultaneously through both.

4. In a cooling system for internal com bustion engines, a source ofsupply of a cooling medium, means for effecting circulation thereof incontact with the cylinders for absorbing heat from the latter, a conduitfor said liquid disposed to heat the latter by the products ofcombustion exhausted from the cylinders, a valve for controlling thecirculation of said liquid to confine the same to either of the said twosources of heat, and thermally actuated means for automaticallyoperating said valve.

5. In a cooling system for internal combustion engines, a source ofsupply of a cooling medium, means for effecting circulation thereof incontact with the cylinders for absorbing heat from the latter, a conduitfor said liquid disposed to heat the latter by the products ofcombustion exhausted from the cylinders, a valve for controlling thecirculation of said liquid to confine the same to either of the said twosources of heat, and means actuated by variations in temperature of theliquid for automatically operating said valve.

' 6. A cooling system for internal combustion engines includingwater-jackets for the engine cylinders, a water conduit associated withthe exhaust manifold for heating water by means of the hot products ofcombustion, a radiator connected with said jackets and conduit fornormally causing the cooling liquid to circulate through said parts, anda valve controlled by the variations in temperature of the liquid forcutting ofi' circulation through the jackets or the conduit or partiallyfrom each.

7. A cooling system for internal combustion engines including the waterjackets of the cylinders and a conduit disposed in heat absorbingrelation to the exhaust gases from said cylinders, a source of supply ofliquid, a single thermostatically actuated valve controlling thecirculation of said liquid for causing the same to pass through eitheror partly through both the jackets and conduits, and means associatedwith said valve for resisting movement thereof in one direction.

8. A cooling system for internal combustion engines including the waterjackets of the cylinders and a conduit disposed in heat absorbingrelation to the exhaust gases from said cylinders, a source of suppl ofliquid, a single thermostatically actuate valve controlling thecirculation of said liquid for causing the same to pass through eitheror partly through both the jackets and con-' duits, and means associatedwith said valve r for resisting movement thereof in one direc- .valve atthe respective limits "of its movement. y

10. A cooling system for internal combustion engines including the waterjackets of the cylinders and a conduit disposed in heat-absorbingrelation tothe exhaust gases from said cyllnders, a radiator, a valvecontrolling the circulation of said liquid for causing the same to passfrom the radiator through either or partly through both the jackets andconduits and back to the radi ator, thermostatically responsive meansconnected with said valve for actuating the same; and cushioning meansinterposed in said connection. I I v 11. In a cooling system forwater-jacketed engines, a water conduit disposed in heat absorbingrelation to the products of combustion exhausted from the engine, aradiator, means for efiecting forced passage of water from the saidradiator to the said conduit and the water jacket of the engine,

' return connection from the latter to said radiator, a valve forcausing a flow from one of said water-heating parts to the exclusion ofthe other, and a temperature responsive element associated with saidvalve for actuating the same. v

12. In a cooling system for water-jacketed engines, a water conduitdisposed in heat absorbing relationto'the products of combustionexhausted from the engine, a radiator, means" for effecting forcedpassage of water from-the said radiator to the said conduit and thewater jacket of the engine, return connection from the latter to saidradiator, a valve for causing a flow through one of said water-heatingparts to the exclusion of the other, and a temperature responsiveelementdisposed in heat-absorbing relation only to the water contained in orflowing through the water jacket and operatively connected with saidvalve for actuating the same.

13. In a cooling system for water-jacketed engines, a water conduitdisposed in heatnaraaoe absorbing relation-to the products of combustionexhausted from the engine, a source of supply of water, means foreffecting forced passage of water from. the said source to the saidconduit and the water jacket of the engine, returncon'nection from thelatter to said source, a valve for causing a flow through one of saidwater-heating parts to the exclusion of the other, a teinperat-ureresponsive element disposgd in heat-absorbing relation to the'waterflowing through the water jacket and operativelyvconnected withsaid valve. for -actuating the same, and means associated with saidconnection for effecting a sudden movement of said valve from oneposition-thereso of to another. I 14. In a cooling system forwater-jacketed engines, awater conduit disposed in heatabsorbingrelation tothe products of com-, bustion exhausted from the engine, asource of supply of water, means for effecting forced passage of waterfrom the said source to the said conduit and the water jacket of theengine, return connection from the latter to said source, a valve forcausing a flow through a temperature responsive element disposed inheat-absorbing relation to the water flowing through the water jacketand operatively connected with said valve for actuating the same, andmeans associated with said connection for effecting a sudden movement ofsaid valve from i one position thereof to another, said means includingmeans for permitting a slow movement of the'valve in all directions ofits movement through apart of the latter after having attained itslast-mentioned position. I

15. In a cooling system for water-jacketed engines, a water conduitdisposed in heatabsorbing relation to the products of combustionexhausted from the engine, a source of supply of water, means foreffecting forced passage of water from the said source to the saidconduit and the water jacket of the engine, return connection from thelatter to said source, a valve for causing a flow through one of saidwater-heating parts to the exclusion of the other, a temperatureresponsive element disposed in heat-absorbing relation to the waterflowing through the water jacket and operatively connected with saidvalve for actuating the same, two sourcesof supply ofhydro-carbon ofdifferent specific gravities for said engine, and

operative connection between the same and said temperature responsiveelement for automatically connecting the latter with the source ofhigher gravity hydro-carbon as the engine tem erature becomessufliciently high to eificient y consume the same. 16. In an internalcombustion engine having water jacketed cylinders constituting differentspecific gravities, a valve adapted to' cut off one of said sources ofsupply as the other is cut in, and a heat responsive element disposed inheat-absorbing relation to the water heated by said cylinders andoperatively connected with said valve to actuate the same.

17. A cooling system'for internal combustion engines including the waterjackets of the cylinders and a conduit disposed in heatabsorbingrelation ,to the exhaust gases from said cylinders, a radiator, a valvecontrolling the circulation of said liquid for. causing the same to passfrom the radiator through either or partly through both the jackets andconduits and back to the radiator, thermostatically responsive meansconnected with said valve for actuating the same, and a check-valveinterposed in the discharge end of the said conduit for preventingback-fiow from the radiator into the same.

18. A cooling system for internal combustion engines including the waterjackets of the cylinders and a conduit disposed in heat-absorbingrelation to the exhaust gases from said cylinders, a radiator, a valvecontrolllng the circulation of said liquid. for causin the same to passfrom the radiator throug either or partly through both the.

jackets and conduits and back to the radiator, thermostaticallyresponsive means connected with said valve for actuating the same, and acheck-valve interposed in the dischari end of said conduit forpreventing bac -flow from the radiator into the same when circulationthrough said conduit is cut off by said temperature responsive means.

, 19. A cooling system for internal combustion engines including thewater jackets of the cylinders and a conduit disposed in heatabsorbingrelation to the exhaust gases from said cylinders, a radiator, a valvecontrolling the circulat'\on of said liquid for causing the same to passfrom the radiator through either or partly through both the jackets andconduits and back to the radiator, thermostatically responsive meansconnected with said valve for actuating the same, and means disposed atthe discharge end of said conduit for preventing back-flow of water fromthe radiator into the same as the circulation through said conduit ,iscut oil by said temperature responsive element.

In testimony whereof I have signed my name in presence 1 of twosubscribing witnesses.

FREDERICK J. RAYFIELD.

